USEFULNESS OF AUTOMATED SERIAL 12-LEAD ECG MONITORING DURING THE INITIAL EMERGENCY DEPARTMENT EVALUATION OF PATIENTS WITH CHEST PAIN

Study objective: To determine whether the use of automated serial 12-l ead ECG monitoring (SECG) is more sensitive and specific than the init ial 12-lead ECG in the detection of injury and ischemia in patients wi th acute coronary syndromes (ACS) during the initial ED evaluation of patients with chest pain. Methods: A prospective observational study w as performed in 1,000 patients with chest pain who were admitted to a university teaching hospital and who underwent continuous ST-segment m onitoring with SECG during the initial ED evaluation. The initial ECG was obtained on presentation, and SECG readings were obtained at least every 20 minutes during the ED evaluation. Diagnostic abnormalities o n the initial ECG were defined as injury or ischemia. Diagnostic chang es on SECG were defined as evolving injury, evolving ischemia, new inj ury, or new ischemia. ACS was defined as acute myocardial infarction ( AMI), recent myocardial infarction, or unstable angina. Results: A dia gnostic SECG was more sensitive than a diagnostic initial ECG for dete ction of AMI (68.1% versus 55.4%; P<.0001) and ACS (34.2% versus 27.5% ; P<.0001). A diagnostic SECG was more specific than a diagnostic init ial ECG for detection of ACS (99.4% versus 97.1%; P<.01). SECG detecte d injury in an additional 16.2% of AMI patients compared with the init ial ECG (61.8% versus 45.6%; P<.0001; 95% confidence interval for diff erence of proportions, 10.9% to 21.4%). Conclusion: SECG during the in itial ED evaluation is more sensitive and more specific than the initi al ECG in the identification of ACS. Patients with a diagnostic SECG n eed intensive antiischemic therapy, evaluation for reperfusion therapy , and admission to an ICU.